Question: What mechanical property of materials starts with the letter "y"?
Paraphrase: What mechanical property of materials begins with the letter "y"?
SPARQL (Wikidata): SELECT DISTINCT ?sbj ?sbj_label WHERE { ?sbj wdt:P31 wd:Q5725005 . ?sbj rdfs:label ?sbj_label . FILTER(STRSTARTS(lcase(?sbj_label), 'y')) . FILTER (lang(?sbj_label) = 'en') } LIMIT 25 
Answer: yield, yield, yield stress, yield stress